Authorities in Burkina Faso have charged an army General who led a failed coup in September 2015 with complicity in the 1987 assassination of the popular ex-leader Thomas Sankara. It follows a pledge by the government to probe the murder.

General Gilbert Diendere (photo), who already stands accused of launching a coup, has now also been formally charged over the murder of former President Thomas Sankara, Burkina Faso’s military tribunal said Sunday.

The charges come amid a renewed push from the West African country’s transitional government to properly investigate the assassination – one of the most high-profile killings in Africa’s post-independence history. As part of the probe, authorities earlier this year exhumed human remains from a grave believed to belong to Sankara.

The former revolutionary leader, sometimes referred to as “Africa’s Che Guevara,” took power in a coup in 1983. He championed a Marxist philosophy, and embarked on reforms to nationalize land and mineral wealth, improve health and education, and reduce debt. In October 1987, he was killed in a coup that brought Blaise Compaore to power.

A senior security source with knowledge of the murder case told Reuters news agency that General Diendere had been charged last month with complicity in the assassination. Charges have also been laid against 10 others, most of whom were soldiers in the elite presidential guard of former President Compaore.

Compaore reversed many of Sankara’s policies and went on to win four elections, all of which were criticized as flawed. He was ousted by protests in October 2014, after attempting to amend the constitution to extend his rule.

Diendere, who served as Compaore’s intelligence chief, led a short-lived coup in September. During the rebellion, soldiers from the presidential guard took the transitional president and prime minister hostage for a number of days.

Several people were killed and more than 250 injured in the anti-coup protests that followed. The presidential guard was subsequently disbanded and Diendere arrested and charged with murder and threatening state security.

The latest charges against Diendere come at a critical moment for Burkina Faso. The West African country, which has been ruled by successive coup leaders since independence in 1960, is currently undergoing a transition to democracy.

In landmark elections at the end of November, voters chose former Prime Minister Roch Marc Kabore to be their next president. Kabore, once an ally of Compaore, went into opposition in early 2014. ref: DW/Reuters/AP